Rotameter construction



Feb. 16, 1943. BOWEN 2,311,181

' ROTAMETER CONSTRUCTION Filed Sept. 6; 1940 2 Sheets-Sheet 1 INVENTOR.

2 13.8% D Bo BY' I ATTORNEY.

Feb. 16, 1943. K. D. BOWEN ROTAMETER CONSTRUCTION Filed Sept. 6, 1940 2 Sheets-Sheet 2 INVENTOR. BY Keane/ D.B0wn

ORNEY.

.ill I k Patented Feb. 16, 1943 ROTAMETER CONSTRUCTION Kenneth 1). Bowen, Midland, Mich, assignor to The Dow Chemical Company, Midland, Mich,

a corporation of Michigan I Application September 6,1940, Serial No. 355,575

I 5 Claims.

The present invention relates to certain new I and'useful constructions and improvements in variable-area rate of flow meters of the tube and float type which are generally referred to in the trade as rotameters.

These rotaimeters are used for accurately measuring the rate of flow of various fluids, and commonly comprise an upright tapered glass metering tube, with its narrower portion lowermost, andhaving a free float member therein adapted to be lifted and suspended in the space inside the tube by'the vertically upward flow of fluid through said tube, with the height reached by the float member indicating the con-current rate of fluid flow. I

One of the objects of the present invention is to provide a rotameter construction which will permit ready and facile removal or replacement of the float-bearing metering tube portion of the rotameter without necessitating either disconnection' of the rotameter in its entirety from the line or substantially complete disassem-bly of the rotameter, and without requiring simultaneous removal and/or disassembly of cumbersome and bulky stufling-box portions commonly provided at the opposite ends of the tube for sealing the end connections thereof. 1

there is shown in the accompanying drawings a form thereof which is at present preferred, since the same has been found in practice to give satisfactory and reliable results, although it is to be understood that the various instrumentalities of which the invention consists can be variously arranged and organized and that the invention is not limited to the precise arrangement and. organization of the instrumentalities as herein shown and described.

Referring now to the drawings, wherein like reference characters indicatelike parts,

Figure 1 represents a perspective view of a rotameter constructed in accordance with the present invention. and comprising one illustrative embodiment thereof, shown disassociated from the fluid-conducting piping which would normally lead thereto and therefrom.

Figure 2 represents a longitudinal sectional view through the rotameter taken on line 2-2 of Figure 1, looking the direction of the arrows.

Figure 3 represents a transverse sectional view taken on broken line 3-"-3 of Figure 2, looking in the direction of the arrows. I

Figure 4 represents a lower transverse sectional view taken on line 4-4 of Figure 2, looking in the direction of the arrows.

Another object of the present invention is to provide a rotameter construction which thoroughly and fully protects the tapered glass metering tube against accidental breakage or in- Jury, and at the same time safeguards theoperator or passers-by against physical injury such asmight otherwise be likely to follow the shattering or breakage of the glass metering tube, particularly should the break occur while the tube had been conveying fluid under extremely high pressures, or when the escaping fluid was of a dangerous character.

Another object of the present invention is to provide a durable compact and simple rotameter I construction whose component parts may be read- 11,; and easily assembled and disassembled as required, and-which when assembled provides a strong and sturdy construction, and which is yet inexpensive to produce.

Another object of the present invention is to provide a rotameter construction having improved packing arrangementsifor sealing the consired, these fittings lllmay have reduced end portions it fitted snugly into corresponding annular recesses in their respectively adjacent end members l4 and ii, in order to insure that the parts will be in their proper relative positions during welding, and to provide a strong andtight connection therebetween.

I If desired, the connection members or fittings I I may be formed integrally with the end members l4 and II, instead of being formed separately therefrom and connected therewith.

The end members I4 and i i may be securely 4 held a fixed distance apart by means of a pair of juxtaposed flat metal side plates l1 and I8, preferably of substantial width, extending intermedi- I ate the end members and securely fastened thereto by bolts l9 screw-threadedly anchored in registering tapped holes in said end members. These of the top end member l4, all as illustrated more particularly in Figures 1 and 3, and the juxtaposed surfaces of these projecting marginal portions may be longitudinally grooved or slotted as at -2| for the reception of the vertical edge portions of a pair of transparent safety plates 22, preferably constructed of shatter-proof glass or the like. These plates 22 are vertically slidable in said grooves, and when operatively disposed therein close the open front and rear portions of the box-like structure 20 while yet permitting observation of the interior thereof.

If desired, the lower edges of these glass plates 22 may rest in grooves on the upper surface of the lower end member I5, or else they may rest whose projecting outer end portions may be screw-threadedly mounted the retaining nuts 29.

The annular sealing members 21 are preferably made from some resilient material, the choice of which may be dictated by the character of the fluids whose rates of flow are to be determined. I have found that sealing rings constructed from Thiokol, which is a synthetic directly on the upper surface of said lower end member. In the preferred embodiment, these safety glass plates 22 are preferably at least coextensive with the front and rear openings of the box-like structure 26 when operatively disposed in the side grooves 2|, thereby completely to cover or obstruct said openings in use.

If desired, only one transparent plate 22 may be provided, with the other plate being replaced by a metal panel either fixedly or movably realted to the other metal plates.

Interiorly of the box-like structure is disposed an upright elongated glass metering tube 23 having a tapered bore with its narrow end lowermost. This metering tube houses a float member 2 The tube 23 is of an overall length preferably slightly less than the distance between the members l4 and I5, and extends intermediate the openings |2 and I3 therein. Each end portion of the tube 23 may be detachably held in fluidtight communication with its respectively adjacent opening by means of an axially adjustable annular clamping collar 26, which crowds a compressible annular sealing member 21 encircling the end of the tube 23 intointimate continuous contact with the end portion of said tube and with the metal surface surrounding the adjacent opening, thereby firmly to seal the joint therebetween and simultaneously to fix the tube end against unintended sidewise displacement relative to said opening. As shown particularly'in Figs. 1' and 2, the annular sealing members 21- extend axially along the tube '23 appreciably beyond the innermost ends ofthe collars, 26.

The clamping collar 26 may have its inner wall tapered in concave frustq-conical fashion, with its larger-diametere end being disposed nearest the adjacent end me ber, and this tapered inner wall of the collar may bear against a corresponding convex A frusto-conically shaped outer surface on the annular sealing member 21, so that rubber-like material, are well suited for general use. If desired, however, the sealing rings may be constructed from other materials, as for example, from Neoprene, Koroseal, or other synthetic or artificial rubber-like materials. Natural rubber may also be used, as may any other suitable material which may be pressed around the joints to seal the same.

If desired, the opening |3 in the lower end member l5 may be of a somewhat smaller diameter than the adjacent lower diameter of the glass metering'tube 23 so that the tube may rest on said lower end member either directly or on a washer 33 disposed therebetween.

In order to limit the vertical movement of the float 24, and to prevent its entering the. piping diameters may be fitted into the end fittings The upper stop 3|' may include a cross-piece 32 extending diametrically across the flow passageway. If desired, however, any other suitable stop means may be provided for limiting the movements of the float member 24.

In actual operation, the fluid flows upwardly into the upwardly tapered glass metering tube 23, and upon encountering the float element 24, lifts said element vertically upwardly to the larger end of the tube establishing a passageway of gradually increasing area around the rim of the float member through which the fluid may pass. The extent to which the float rises verticallyin the metering tube is proportional to the rate .of fluid flow, with each particular rate of flow having a corresponding float position.

The metering tube 23, which may be constructed from Pyrex or other glass or from suitable transparent plastic material, may have a calibrated scale (not shown) fused, etched, or otherwise marked thereon for indicating either the vertical height of the float member, or for directly indicating the corresponding rate of flow.

When it is desired to replace the glass metering tube 23 with another tube of the same or of different size, orwhen it is desired to remove the tube 23 in order to gain access to the fioatmember 24 or to clean the tube'member or the float member, or for any other reason, all that need be done is first t0 remove one of the protective glass plates 22 by sliding it upwardly out of its retaining grooves 2| and then unscrew the retaining nuts 29, thereby loosening the clamping collar 26. The bolts 28 may then be removed and the glass metering tube 23 then bodily extracted transversely from the box structure, carrying with it the end sealing members 21 and associated collars 26. If desired, this sidewise extraction of the metering tube may be somewhat facilitated by first sliding the sealing members 21 axially along the metering tube to some slight extent before drawing said tube sidewise from the box structure.

The foregoing construction permits ready and facile removal or replacement of the metering tube without necessitating disconnection of therotameter from the line, and without requiring any substantial disassembly of the rotameter and sition to provide access to the interior of said i involves merely the removal of the bolts and nuts 28 and 29.

The surrounding box-like'structure amply and fully protects the metering tube against being accidentally broken from without, while yet exposing it to view. Furthermore, if the metering tube should accidentally break due to some internal cause as for example due to an internal explosion or the-like, the surrounding box-like structure 20 and the associated juxtaposed glass safety plates 22 will confine the force of the explosion and/or the fluid flow, at least temporarily, thereby avoiding possibly serious injury to persons in the imme-' diate vicinity thereof. The hereinabove described protective structure which fully encases the metering tube 23 is of particular importance in high pressure lines or where the hazard of breakage of the tube may be unusually great, as for example in the handling of highly volatile and highly inflammable and explosive fluids, or in the handling of poisonous or dangerous fluids whose accidental escape may cause great damage.

The foregoing simple and compact rot-ameter construction is extremely durable and sturdy, permits ready assembly or disassembly of component elements, and yet may be produced at relatively low cost.

The present invention may be embodied in structure, said top and bottom end membershaving aligned openings therein, a tapered, transparent metering tube 01' length sufllciently short to permit it to be moved sidewise between said top and bottom members, extending intermediate said aligned openings, and sealing means at'each end of said tube sealing around the joints between said -tube and'said openings,v said sealing means each being detachably associ-ated with said structure and each comprising surrounding the adjacent opening, and an axially adjustable clamping collar detachably.

connected with the adjacent end'member press-- ing said sealing member radially inwardly into intimate sealing engagement with the tube wall and axially into intimate sealing engagement .with the juxtaposed metal surrounding said adv jacent opening.

3. A fluid flow meter including an upright rec tened thereto, opposed front and rear marginal other specflc, forms without departing from the spirit or essential attributes thereof. and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive, reference being had to the appended claims rather than to the foregoing description to indicate the scope of the invention.

Having thus described my invention whatis hereby claimed as new and desired to be secured by Letters Patent is:

1. A fluid flow meter including a pair of horizontal opposed upper and lower metal end members each having an opening contrally disposed therein, right and left metal side plates extending intermediate said upper and lower end members and rigidly connected therewith, front and rear side plates extending intermediate the opposed front and rear marginal portions of said right and left side plates, said members and plates comof an overall length slightly less than the dis- 2. A flu id flow meter, including an upright rectangular box-like structure having top and bottom end members and four side panels com- -=positely defining a generally enclosed chamber.

. juxtaposition with the surface surrounding the 1 an-opposed pair of said sidezpanels being made.

portions in said metal side plates bearing vertical grooves, and a pair of juxtaposed transparent front and rear plates having their vertical edge portions extending into said grooves, said transarent plates each being vertically slidably reovable from said grooves to provide access to the interior of said structure, said top and bottom end members having aligned openings therein, a tapered, transparent metering tube of length sufllciently short to permit it to be moved sidewise between said top and bottom members, extending intermediate said aligned openings, and sealing means at each end of said tube sealing around the joints between said tube and said openings, said sealing means each being detachably associated with said structure and, each comprising an annular compressible sealing member encircling an end of said tube and having a portion in operative juxtaposition with the metal surrounding the adjacent opening, and an axially adjustable clamping collar detachably connected with the adjacent end member pressing said sealing member radially inwardly into intimate sealing engagement with the tubewall and axially into intimate sealing engagement with the juxtaposed metal surrounding said ad.- jacent opening. 1 g

4; A fluid flow meter comprising an upright structure including top and bottom endmembers having aligned openings therein and side-walls, said structure defining a generally enclosed chamber, a tapered transparent metering tube otlength sufllcien'tly short to permit it to be moved sidewise between said top and bottom end members extending intermediate said-aligned openings, means formingpart of saidstructure and permitting opening thereof for sidewise removal of said tube, and sealing means at each end of said tubefor peripherally sealing the pressible sealing. member encircling an end of said tube and having -a portion in operative adjacent opening, an axially adjustable clamping collar detachably connected with the adjacent end member pressing said sealing member radially inwardly into intimate sealing engagement with the tube wall and axially into intimate sealing engagement with the juxtaposed surface surrounding said, adjacent opening, and screwthreaded means extending through said end member and operable from outside of said structure for axially adjusting said clamping collar.

5. A-fluid flow meter of the character described including metal end members in spaced relationship to each other: and having aligned openings therein, a transparent tapered metering tube of overall length slightly less than the distance beposition with said said ends and having portions in operative juxtaend members, annular having imam-conical inner surf-aces encircling said pliable sealing elements and adapted in force said sealing elements against said end members. and adjustable means detachably holding said collars to said end members, said collars being spaced substantially apart from the adjacent portions oi said metering tube, said sealing elements extending axially inwardly along said metering tube from said end members substantially beyond the innermost ends of said collars,

tween said end members and having its ends in operative juxtaposition with the openings in said end members and generally perpendicular thereto, annular pliable sealing elements encircling said collans exerting pressure upon said sealing elements only along the i'rusto-oonical inner surfaces thereof.

KENNETH D. BOWEN.

collars 

